User manual XTA DP548 DATASHEET

[. . . ] INPUT SECTION Sub-menu: Set up input ganging, and GEQ `Q' setting. CROSSOVER Sub-menu: Set up or adjust crossover design, including routing and auto limiter setting. SYSTEM Sub-menu: Used to view unit's status, and select various global options such as PEQ `Q' or bandwidth units, delay units, and output metering point (pre/post mute). SECURITY Sub-menu: Used for locking various operations of the unit, using a 4 digit code. [. . . ] They can be thought of as listening to and acting upon all information addressed to them, but not replying. Up to 128 shadow units may be connected and assigned the same ID as the `main' unit, but remember that the maximum total units on any one RS485 network is 128. Shadow ID numbers are accessible when the unit's interface is configured, and will appear after ID number 128, starting from 1 again, but designated shadow IDs with an `s' after the number ­ 1s. Any ID can have multiple corresponding shadows. RS485 Interface This interface is fitted as standard to all units and is accessed via the 3-pin XLR sockets on the rear of the unit. Cables to connect units together or to an RS232-485 converter will need to be wired one-to-one. We recommend the use of standard shielded microphone cables, or a balanced feed from a multicore. RS485 is a fully balanced system, capable of sending data over distances of up to one kilometre. The RS485 output of each unit is purely hardwired from the input and so no electrical regeneration of the signal is provided. What this means is that the distance from the first RS485 output to the last RS485 input must not exceed 1km in total. As this diagram illustrates ­ The combined length of cables 01 + 02 + . . . NN < 1000 metres. XTA has a range of tried and tested interfaces, all of which are listed in the XTA Interface Guide, available from our website. The letter after each is the silicon version (and is of no importance to the user). Pressing ENTER again will show AES Device Status V : 96k0 V : 96k0 This display shows the status of the two AES receivers, input A on the left, and Input C on the right. The sample rate the unit has been able to lock to is shown, or UNLOCKED will be displayed in its place. The unit will lock to sample rates from 32kHz up to and including 192kHz. The unit's own processing sample rate is 96kHz, and AES output data is always at 96kHz. Internal sample rate converters will translate all incoming rates to 96kHz ­ one converter for each AES input. This allows the two input streams to be at different rates if necessary. Page 34 DP548 Operator's Manual Security and Locking ENTER, After selecting the Security Sub Menu and pressing ENTER select one of the lock types, choosing the most appropriate one for your application. User Specific Upon pressing ENTER to select this type of lock, each parameter group is presented in turn. Choose the type of lock (as above) using the FREQ encoder, and press ENTER to confirm each parameter. The description of this operation is given at the end of this section. This option allows the user to specify, for each type of parameter, whether it is to be completely accessible (`No Lock'), viewable but not adjustable (`Control'), or effectively unavailable (`Display'). [. . . ] Remember that `Q' is 1/Bandwidth, so the higher the `Q', the lower the Bandwidth, and the smaller the range of frequencies affected. The filter is primarily 12dB/Octave, but in achieving this sort of roll-off with a high `Q' value will result in quite a large overshoot in level at the turnover frequency. This type of filter is often also called a resonant filter. Operator's Manual Page 57 ¤¤ ¤¤ ££ ££ ¢¢ ¢¢ ¡¡ ¡¡ Elliptical filters InA Input A HPF:1/~~ 1k00Hz HP Ellip Remember ­ to change filter types, press BYPASS to bypass the filter, and then use ENTER to select the filter type. This sets the 3dB point of the filter which features a steep roll-off (of approx 36dB/Octave down to one Octave above (or below in the case of a HPF) the turnover frequency. [. . . ]